A Northern Desert Nightsnake crawls across an old cement highway into the desert.

Description

Not Dangerous (Non-poisonous) - Mildly venomous, but not considered harmful to most humans.

Size

Adults can be 12 - 26 inches long (30-66 cm.) Most seen are 8 - 12 inches long, rarely over 16 inches.
Hatchlings are about 7 inches in length.

Appearance

A small slender snake with a narrow flat head, smooth scales in 21 rows, and vertical pupils.

Color and Pattern

Color varies, often matching the substrate, from light gray, light brown, beige, to tan or cream, with dark brown or gray blotches on the back and sides.
Usually a pair of large dark markings on the neck and a dark bar through or behind the eyes.
Whitish or yellowish and unmarked underneath.

Life History and Behavior

Activity

Nocturnal, and also active at dusk and dawn.
Can be found under rocks, boards, dead Joshua tree branches, and other surface objects.
Often seen crossing desert roads on warm nights.

Diet and Feeding

Eats a wide range of terrestrial vertebrates, mostly lizards and their eggs, sometimes small snakes, frogs, and salamanders.

Breeding

After mating, females lay a clutch of 2-9 eggs from April to September. (Stebbins, 2003)
Eggs hatch in 50-65 days. Hatchlings are about 7 inches in length. (Bartlett & Tennant, 2000)

Habitat

Found in a variety of habitats, often arid areas, from chaparral, Sagebrush flats, deserts, suburban lots and gardens, mountain meadows, grassland.
Most commonly found in areas with abundant surface cover.

Geographical Range

This subspecies, Hypsiglena chlorophaea deserticola - Northern Desert Nightsnake, is found throughout southern California, north to San Luis Obispo County, east and north along the western Sierra Nevada mountains, and into the Great Basin desert in the far northeast part of California, including Lava Beds National Monument. There is also a record for Siskiyou county north of Yreka near the Oregon Border. Outside of California, it ranges south into Baja California, east throughout the southwest, and north into Washington.

Mulcahy, 2008, conducted a comprehensive genetics study of Hypsiglena, recognizing 6 species, three in the USA, and an undescribed species, all from the one previous species of Hypsiglena torquata. He also maintained several subspecies designations. Within California: H. chlorophaea, and H. ochrorhyncha "…were each recovered as groups of multiple subspecies. The subspecies within these wide-ranging species were maintained pending further evaluation. These subspecies may represent incipient species that may not yet have achieved reciprocal monophyly, but possess unique morphologies, and are geographically discrete." 1

Wright, Albert Hazen & Anna Allen Wright. Handbook of Snakes of the United States and Canada. Cornell University Press, 1957.

Conservation Status

The following status listings are copied from the April 2018 Special Animals List and the 2017 Endangered and Threatened Animals List, both of which are published by the California Department of Fish and Wildlife.

If no status is listed here, the animal is not included on either CDFW list. This most likely indicates that there are no serious conservation concerns for the animal. To find out more about an animal's status, you can go to the NatureServe and IUCN websites to check their rankings.